过渡金属镍（铁）磷化物的制备及其催化性能研究

发布时间：2018-05-20 02:40

  本文选题：Ni_2P + 析氧反应　； 参考：《西华师范大学》2017年硕士论文

【摘要】：过渡金属磷化物材料应用广泛,在催化、磁学、陶瓷材料、光、和电子等领域均具有较好的发展。被普遍认为是新型绿色催化剂的潜在材料。本论文采用一步热解次磷酸钠和过渡金属镍源的方法制备了廉价的磷化镍,并研究了这些材料的形貌和物相结构以及在电催化分解水、活化过一硫酸盐降解有机染料、催化还原对硝基苯酚的性能。具体研究内容如下:通过次磷酸钠磷化镍铁草酸盐,制备了不同镍铁比例的磷化物NixFe2-xP(x=2,1.5,1.0,0.5,0),研究了它们在碱性条件下的OER性能,电化学测试表明镍铁磷化物固溶体均表现出比单一的Ni_2P、Fe2P更好的电催化活性,其中Ni1.5Fe0.5P簇状纳米片的电催化活性最佳。电流密度为10 mA cm-2时,具有较低的过电位285 mV,和较小的塔菲尔斜率51.9 mV dec-1。计时电压数据说明Ni1.5Fe0.5P具有较好的稳定性。采用Ni_2P活化过一硫酸盐(PMS)的方法降解染料MB,实验表明Ni_2P/PMS体系比单一的Ni_2P或PMS有更高去除效果,证实Ni_2P确实能够催化PMS。而且在一定范围内,Ni_2P/PMS体系中无论增加Ni_2P或者PMS的用量都会促进MB的降解。在30℃时,含量为150 mg L-1的Ni_2P/PMS能够将100 mg L-1的MB在很短的时间内将其降解完全。用甲醇和叔丁醇作自由基猝灭剂进行猝灭实验,结果证明体系中起氧化作用的活性成分主要是SO4· 。根据阿伦尼乌斯方程计算出Ni_2P/PMS体系活化能为37 kJ/mol,低于文献报道值。循环实验说明Ni_2P具有较稳定的催化性能,回收利用率高。以次磷酸钠为磷源,制备Ni_2P催化剂,用XRD,SEM,EDS,TEM,XPS对其物相结构、形貌及组成进行了表征,研究其在硼氢化钠还原对硝基苯酚中的催化作用,结果表明,直径在20~100 nm的Ni_2P纳米颗粒具有非常好的催化性能,有一个较大的反应速率常数1.0343 min-1,催化剂的循环实验说明Ni_2P具有很好的重复使用稳定性。又以同样的实验方法证明了Ni_2P对催化还原罗丹明B也有很好的催化效果及循环稳定性。
[Abstract]:Transition metal phosphates are widely used in many fields, such as catalysis, magnetism, ceramics, light and electronics. It is widely considered as a potential material for new green catalysts. In this paper, cheap nickel phosphide was prepared by one step pyrolysis of sodium hypophosphite and transition metal nickel source. The morphology and phase structure of these materials were studied. Catalytic reduction of p-nitrophenol. The specific research contents are as follows: through sodium hypophosphate nickel ferronickel oxalate, the phosphates NixFe2-xPxPnxH2HX with different ratios of NixFe2-xPnxH2HX were prepared, and their OER properties under alkaline conditions were studied. The electrochemistry test showed that the nickel iron phosphate solid solution had better electrocatalytic activity than the single Ni _ S _ 2P _ 2P _ 2P _ 2P _ 2P _ 2P _ 2P _ 2P _ 2P _ 2P _ 2P _ 2P _ 2P _ 2P _ 2P _ 2P _ 2P _ When the current density is 10 Ma cm-2, the overpotential is 285mV and the Taffel slope is 51.9 MV dec-1. The timing voltage data show that Ni1.5Fe0.5P has good stability. The dye MBs were degraded by Ni_2P activation. The experimental results show that the Ni_2P/PMS system has higher removal efficiency than the single Ni_2P or PMS system. It is proved that Ni_2P can catalyze PMSs. In addition, in a certain range of Ni2P / PMS systems, increasing the amount of Ni_2P or PMS can promote the degradation of MB. At 30 鈩，

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